Structure of the neutral pion and its electromagnetic transition form factor

Abstract

The ${\gamma }^{\ast }\gamma \to {\pi }^0$ transition form factor, $G(Q^2)$, is computed on the entire domain of spacelike momenta using a continuum approach to the two valence-body bound-state problem in relativistic quantum field theory: the result agrees with data obtained by the CELLO, CLEO and Belle Collaborations. The analysis unifies this prediction with that of the pion's valence-quark parton distribution amplitude (PDA) and elastic electromagnetic form factor, and demonstrates, too, that a fully self-consistent treatment can readily connect a pion PDA that is a broad, concave function at the hadronic scale with the perturbative QCD prediction for the transition form factor in the hard photon limit. The normalisation of that limit is set by the scale of dynamical chiral symmetry breaking, which is a crucial feature of the Standard Model. Understanding of the latter will thus remain incomplete until definitive transition form factor data is available on $Q^2>10$GeV${}^2$.

9 pages, 2 figures

References in corpus (10)

• Hadronic Spectra and Light-Front Wavefunctions in Holographic QCD
• Determination of the Charged Pion Form Factor at Q2=1.60 and 2.45 (GeV/c)2
• Charged pion form factor between Q^2=0.60 and 2.45 GeV^2. II. Determination of, and results for, the pion form factor
• Measurement of gamma gamma* --> pi0 transition form factor at Belle
• Abelian anomaly and neutral pion production
• Moments of pseudoscalar meson distribution amplitudes from the lattice
• Light Cone Sum Rules for the pi0-gamma*-gamma Form Factor Revisited
• A New Measurement of the ${\pi }^0$ Radiative Decay Width
• Comparing antithetic trends of data for the pion-photon transition form factor
• A combined study of the pion's static properties and form factors

Cited by in corpus (72)

• The anomalous magnetic moment of the muon in the Standard Model
• Dispersion relation for hadronic light-by-light scattering: pion pole
• 50 Years of Quantum Chromodynamics
• Insights into the Emergence of Mass from Studies of Pion and Kaon Structure
• Pion-pole contribution to hadronic light-by-light scattering in the anomalous magnetic moment of the muon
• The pion: an enigma within the Standard Model
• Process-independent strong running coupling
• Kaon-box contribution to the anomalous magnetic moment of the muon
• Hadron tomography by generalized distribution amplitudes in pion-pair production process ${\gamma }^{\ast }\gamma \to {\pi }^0{\pi }^0$ and gravitational form factors for pion
• Symmetry, symmetry breaking, and pion parton distributions
• Empirical Consequences of Emergent Mass
• Pion and kaon valence-quark quasiparton distributions
• ${\gamma }^{\ast }\gamma \to \eta ,{\eta }^{\prime }$ transition form factors
• Impressions of the Continuum Bound State Problem in QCD
• QCD Running Couplings and Effective Charges
• Mass-dependence of pseudoscalar meson elastic form factors
• Exposing strangeness: projections for kaon electromagnetic form factors
• Partonic structure of neutral pseudoscalars via two photon transition form factors
• Elastic electromagnetic form factors of vector mesons
• Quark-gluon Vertex: A Perturbation Theory Primer and Beyond
• Single pseudoscalar meson pole and pion box contributions to the anomalous magnetic moment of the muon
• Drawing insights from pion parton distributions
• Contact interaction analysis of pion GTMDs
• Contribution of neutral pseudoscalar mesons to $a_{\mu }^{HLbL}$ within a Schwinger-Dyson equations approach to QCD
• Pseudoscalar pole light-by-light contributions to the muon $(g-2)$ in Resonance Chiral Theory
• ${\eta }_c$ Elastic and Transition Form Factors: Contact Interaction and Algebraic Model
• Nucleon elastic form factors at accessible large spacelike momenta
• Transverse Takahashi Identities and Their Implications for Gauge Independent Dynamical Chiral Symmetry Breaking
• Systematic estimation of theoretical uncertainties in the calculation of the pion-photon transition form factor using light-cone sum rules
• Distribution Amplitudes of Heavy Mesons and Quarkonia on the Light Front
• Heavy quarkonia in a contact interaction and an algebraic model: mass spectrum, decay constants, charge radii and elastic and transition form factors
• Off-shell persistence of composite pions and kaons
• On the large-Q^2 behavior of the pion transition form factor
• Distribution amplitudes of radially-excited pi- and K-mesons
• Pion and Kaon box contribution to $a_{\mu }^{\text{HLbL}}$
• Spectrum and structure of octet and decuplet baryons and their positive-parity excitations
• Aspects of open-flavour mesons in a comprehensive DSBSE study
• Two Photon Transition Form Factor of $\bar{c}c$ Quarkonia
• Pion-photon transition form factor in LCSR and tests of asymptotics
• Pseudo-scalar mesons: light front wave functions, GPDs and PDFs
• Spacelike and timelike form factors for the $({\pi }^0,\eta ,{\eta }^{\prime })\to {\gamma }^{\ast }\gamma$ transitions in the light-front quark model
• Improved ${\pi }^0,\eta ,{\eta }^{\prime }$ transition form factors in resonance chiral theory and their $a_{\mu }^{\mathrm{HLbL}}$ contribution
• Effect of the Quark-Gluon Vertex on Dynamical Chiral Symmetry Breaking
• The impact of transverse Slavnov-Taylor identities on dynamical chiral symmetry breaking
• Quark anomalous magnetic moment and its effects on the $\rho$ meson properties
• A fresh look at the (non-)Abelian Landau-Khalatnikov-Fradkin transformations
• Nucleon Quark Distribution Functions from the Dyson-Schwinger Equations
• $D^{\ast }$ and $D_s^{\ast }$ distribution amplitudes from Bethe-Salpeter wave functions
• How gauge covariance of the fermion and boson propagators in QED constrain the effective fermion-boson vertex
• The time-like electromagnetic kaon form factor
• Light-front Wave Functions of Vector Mesons in an Algebraic Model
• Calculation of the pion-photon transition form factor using dispersion relations and renormalization-group summation
• The Podolsky propagator in gap and bound-state equations
• Hadron Structure using Continuum Schwinger Function Methods
• Emergent phenomena and partonic structure in hadrons
• The quark spectral functions and the Hadron Vacuum Polarization from application of DSEs in Minkowski space
• Heavy-light mesons spectra in a contact interaction
• Radially excited pion: electromagnetic form factor and the box contribution to the muon's $g-2$
• Gauge Technique approximation to the $\pi \gamma$ production and the pion transition form factor
• An updated determination of the pion-photon transition form factor
• Pseudoscalar current and covariance with the light-front approach
• Gravitational form factors in the perturbative limit
• Extracting a model quark propagator's spectral density
• Improved estimates of the pion-photon transition form factor in the $(1\le {\mathbf{Q}}^2\le 5)$~GeV${}^2$ range and their theoretical uncertainties
• Pion observables calculated in Minkowski and Euclidean spaces with Ansätze for quark propagators
• S- and D-wave vector charmonia
• Two photon transition form factors of neutral pseudoscalar mesons
• Pion transition form factor through Dyson-Schwinger equations
• Regarding the distribution of glue in the pion
• Baryonic form factors of light pseudoscalar mesons
• $D^{\ast }D\pi$ and $B^{\ast }B\pi$ couplings from Dyson-Schwinger equations framework
• Quark-photon vertex from lattice QCD in Landau gauge